Adv. Eng. Tec. Appl. 4, No. 2, 15-25 (2015) 15 Advanced Engineering Technology and Application An International Journal

http://dx.doi.org/10.12785/aeta/040202

Fabrication and Applications of Fiber Bragg Grating- A Review

Sanjeev Dewra1, Vikas2 and Amit Grover2,∗ SBSSTC Ferozepur, Punjab, 152004, India

Received: 24 Sep. 2014, Revised: 17 Mar. 2015, Accepted: 19 Mar. 2015 Published online: 1 May 2015

Abstract: In this paper, the brief introduction of Fiber Bragg Grating, its significant applications, sensing principles, properties, fabrication and the basic designing of FBG have been discussed. FBG’s are relatively simple to manufacture, small in dimension, low cost and exhibits good immunity from the electromegnatic radiations. The former inceptions and the essential techniques of fiber Bragg grating fabrication are described. This paper presents a comprehensive and systematic overview of FBG technology.

Keywords: Fiber Bragg grating, Current applications of Fiber Bragg Grating, Fiber Bragg Grating sensors.

1 Introduction

A Fiber Bragg Grating is revealing the core of SMF to a periodic model of passionate ultra violet light. The spotlight generates a stable increase in the of the core of fiber to produce a fixed index modulation in the direction of the exposure pattern and this fixed index modulation is known as grating. At each periodic small amount of light is reflected. When the grating period is about half the input of light, all the reflected light signals merge comprehensibly to Fig. 1: Fiber Bragg grating in optical fiber[3] one large reflection at a specific channel. This is known as the Bragg condition. The development of permanent grating in optical fiber was first introduced by Hill et al. in 1978 at Canadian communication research centre, strain by stretching fiber and as a feedback mirror for Ottawa, Canada [1,2]. The FBG is depicted in Fig 1. By . The photosensitivity was overcome by Meltz et al. temperature and strain tuning of FBG, Spectral [3] who acknowledged from the work of Garside and measurement is not done directly. A narrowband Bragg Lam [4] that it was a 0two photon process, which could grating filter had been created over entire 1m length of be made much more proficient if it was a one photon fiber, known as Hill grating. process at a wavelength in the 245 nm Germania oxygen-vacancy defect bands [5]. The wavelength of the UV light is 244 nm that corresponds to one half of 488 1.1 Formation of Grating and Fabrication nm, to generate the Hill gratings the wavelength of the Techniques blue argon laser line used [6]. In the core of the fiber, the two overlapping UV light beams interfere generating a For use in fiber optic communication it was recognize that periodic interference pattern that has equivalent periodic grating in an optical waveguide have numerous potential index grating. This technique is known as the transverse applications in the fabrication of devices and it was holographic technique. The two beam interferometer depicted that ”Hill grating” could be used as a sensor for arrangement for side-writing FBG is shown in fig 2.

∗ Corresponding author e-mail: amitgrover [email protected]

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Fig. 3: Bragg grating fabrication apparatus based on a zero order null phase mask. The duty cycle of the phase mask is chosen to be 50% [7]

Fig. 4: Fiber Bragg for reflection of the incident mode at the λ [9]

Fig. 2: Two-beam interferometer arrangement for Side-writing FBG [5] methods have been superseded by the phase mask technique is prepared from flat slab of silica glass that is transparent to UV light [10]. The optical fiber is located in contact with corrugation of the phase as depicted in the The holographic technique for grating fabrication has figure no. 3 UV light that is incident normal to the phase two principle advantages. Bragg grating could be photo mask passes via a periodic corrugation of the phase mask imprinted in the core of fiber without removing the glass [7]. Generally, most of the deflected light is enclosed in cladding. Moreover, the period of the photo induced the 0, +1 and -1 diffracted orders. Though, the phase grating depends upon the angle between the two mask is design by controlling the depth of the corrugation interfacing coherent light beams. Thus even in the phase mask, to suppress the diffraction into the zero through UV light is used to fabricate the grating, Bragg order. Experimentally in the zero-order the amount of grating could be made to function at much longer light can be decreased to less than 5% with approximately in a spectral region of interest for devices 40% of the total light intensity divided equally in the 1 that have application in fiber optic communication and orders. The two 1 diffracted order beams interfere to optical sensors [8]. produce a periodic pattern that photo imprints an Previously, FBG was first fabricating using the equivalent grating in the optical fiber [8]. This period is internal writing [1] and holographic technique [3]. These independent of the wavelength of ultra violet light

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irradiating the phase mask corrugation depth required to attain light is a function of the wavelength and the optical . The phase mask method has the improvement of simplifying the manufacturing procedure for Bragg grating with a high performance. In contrast with the holographic system, the phase mask method provides easier alignment of the fiber for lower coherence requirements. The Bragg wavelength of the fiber will shift by 2nm. The phase mask technique is very flexible in that it can be used to fabricate gratings with controlled spectral response characteristics [11]. For example, the spectral response of finite length grating with a uniform index modulation along the fiber length has secondary maxima on both sides of the main reflection peak [12]. If the shape of the index modulation along the fiber length is given a bell-like functional shape, these secondary Fig. 5: FBG in OFC system maxima can be suppressed this process is known as apodization [13]. Apodized fiber gratings have been fabricated using the phase masks techniques and suppressions of the side lobes of 30-40 db have been The recent applications of the FBG are: achieved [14,15]. The phase mask techniques have also –Fiber Bragg Grating for Dense WDM been extended to the fabrication of apodized fiber grating. –Fiber Bragg Grating for optical add drop multiplexer Aperiodic or chirped grating are desirable for making –Fiber Bragg Grating as erbium-doped fiber amplifier dispersion compensators [16]. Another approach to Pump laser stabilizer grating fabrication is the point-by-point technique [17]. In –Fiber Bragg Grating as Optical amplifier gain this method each index perturbation of the grating are flattening filter written point-by-point. However, it has been used to fabricate micro-Bragg grating in optical fiber [18] but is most valuable for making coarse gratings with pitches of 2.1 Fiber Bragg Grating for dense wavelength the order of 100m that are required LP modes converters and polarization mode converters [19]. Because of their division multiplexing use in long period fiber grating band-rejection filters and fiber amplifier gain equalizer the interest in coarse period To attain greater spectral efficiency value and total grating has increased [20]. information capacity and to reduce the performance degradation caused by transmission impairments, the system investigation is of great importance. Therefore it is 1.2 Fundamental Properties of Gratings essential to calculate dense WDM transmission for broadband access. Furthermore it is important to evaluate In the core of fiber, the index perturbation is a periodic Dense WDM direct system parameters with currently structure identical to a volume hologram or a crystal available and reasonable priced optical components [23]. lattice that act as a stop-band filter [8]. A narrow band of The fiber Bragg grating technology performs vital role in the incident optical field within the filter is reflected by DWDM system. With the help of the fiber Bragg grating successive, coherent scattering from the index variations we can filter out the particular wavelengths from the [21,22]. Each reflection from a crest in the index system as shown in the Fig. 6 perturbation is in phase with the next one at ?B, as depicted in Fig.4 and any change in fiber properties like temperature, strain that varies the modal index or grating 2.2 FBG for OADM pitch will change the Bragg wavelength [9]. The grating filter characteristics can be understood and modeled by An Optical add drop multiplexer is a device that used in numerous approaches . WDM systems for multiplexing and routing different channels of light into or out of a SMF. This is a type of optical node, that is normally used for the production of 2 Current Applications of FBG optical telecommunications networks. Add/remove here refer to the ability of the device to add one or more new Fiber Bragg grating performs very important role in the channels to an existing multi-wavelength WDM signal optical fiber communication system. The possible use of and to remove one or more channels, passing those FBG in communication system as shown in Fig. 5 signals to another path of network [24]. A traditional

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Fig. 6: FBG in DWDM system [23] Fig. 7: OADM with the help of FBG[25]

Optical Add/Drop Multiplexer comprises three stages such as an optical demultiplexer, an optical multiplexer manufacturing, this approach has proven to be practical and between them a method of reconfiguring the routes and cost-effective [26]. between the optical demultiplexer, the optical multiplexer and a set of ports for adding and removing signals. The The feedback from the Fiber Bragg Grating is efficient demultiplexer separates wavelengths in an input fiber onto if the light reflected into the semiconductor laser cavity has ports. The reconfiguration can be achieved by optical the proper Transverse-electric polarization [27]. A change switches that direct the wavelengths to the optical of the state of polarization upon propagation in the fiber multiplexer or to drop ports. The multiplexer multiplexes can result in a loss of effective feedback [28]. The FBG- the wavelength that are to persist on from demultipexer stabilized pump laser component is shown in Fig. 8. ports with those from the add ports, onto a single output fiber [25]. All the light paths that directly pass OADMs are termed cut-through light paths, while those that are added or removed at the optical add drop multiplexer node are named added/removed light paths. Physically, there are numerous ways to realize an optical add-drop multiplexer. There are a variety of demultiplexer and multiplexer technologies including thin film filters, fiber Bragg gratings with optical circulators, free space grating devices and integrated planar arrayed waveguide gratings. The switching or reconfiguration functions range from the manual fiber patch panel to a variety of switching technologies including microelectromechanical systems, liquid crystal and thermo-optic switches in planar waveguide circuits. The optical add drop multiplexer with Fig. 8: Schematic of an FBG-stabilized pump laser module. the help FBG is depicted in Fig. 7 Rb, R f , and Rg denote the back, front, and FBG power reflectivity[29]

2.3 FBG as EDFA Pump laser stabilizer

The properties of an EDFA depend on the characteristics The distance between laser chip and Fiber Bragg of the pump laser diode. Today, FBGs are a standard Grating is normally 0.5 to 2 m [30]. This is important for passive component for wavelength and power emerging 980-nm pump laser applications like uncoupled stabilization of 980-nm pump . The general for one-for-two-replacement pump schemes in EDFAs technology for fiber Bragg grating stabilized pump laser with increasingly stringent requirements on performance, modules is one that uses a standard SMF. In large-scale regarding power and wavelength stability [31].

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2.4 FBG as optical amplifier gain flattening interference and transmission loss that make their usage filter challenging in many applications. Optical fiber sensing is the best solution to these challenges, using light as EDFAs enabled the wide-ranging deployment of Dense compare to electricity and standard optical fiber instead of Wavelength Division Multiplexing networks. copper wire [32]. The magnificent amount of innovation Advancements in EDFA performance reduce have over the last two decades in the fiber-optic allowed for longer fiber links between regenerators. To communication and optoelectronics industries has the cost of regeneration efforts are ongoing to improve significantly reduced optical component prices and amplifier performance. For optical amplifiers, gain enhanced quality. The fiber-optic sensor works by flatness is necessary to mitigate optical signal-to-noise modulating one or more properties of a propagating light and non-linear effects in Dense Wavelength Division wave, intensity, including phase, polarization and Multiplexing networks. To equalize gain, an appropriate frequency in response to the environmental parameters to Gain flattening filter with a spectral response matching be measured. Intrinsic optical sensors utilize the optical the inverse Gain profile is incorporated within the fiber itself as the sensing element. The most commonly amplifier. used optical sensors are the fiber Bragg grating that Among the technologies available for fixed gain reflects a wavelength of light in response to variations in flattening, the most widely employed are based on strain and temperature. FBGs are constructed by using a thin-film dielectrics and fiber grating. GFFs based on fiber phase mask or holographic interference [33]. When a gratings include chirped Bragg gratings, slanted Bragg broad light beam is send to FBG, reflections from each gratings, and long-period gratings. GFFs have a segment of alternating refractive index interfere significant impact on the level of gain ripple amplifier constructively only for a definite wavelength of light, manufacturers can specify for their devices. The known as Bragg wavelength, described in equation. This accumulation of gain ripple in a fiber optic link spanning effectively causes the FBG to reflect a specific frequency many amplifiers will require regeneration of the optical of light while transmitting all others. signal periodically across the network. Signal λ = Λ regeneration imposes significant cost and complexities on b 2n (1) the network. Proper selection of fixed GFFs can allow In equation (1), n is the effective refractive index of amplifier manufacturers to reduce gain ripple, thus λ Λ offering significant economic benefits. the core, b is the Bragg wavelength, and is the spacing between the fiber gratings, called the grating period. As shown in the Fig. 9 The Bragg wavelength is a function of the spacing between the gratings, Changes in temperature and strain affect both the grating period (Λ) and effective refractive index (n) of a Fiber Bragg Grating that results in a shift in the reflected wavelength [34]. The change of wavelength of Fiber Bragg Grating due to temperature and strain can be approximately described by equation (3). Where λo is the initial wavelength and ∆λ is the wavelength shift. This expression shows the impact of strain on the wavelength shift, where ρe is the strain-optic coefficient ∆T is the temperature coefficient and ε is the strain experienced by the grating. The second expression describes the impact of temperature on the wavelength shift, where αΛ is the thermal expansion coefficient and αn is the thermo-optic coefficient. αn Describes the change in refractive index while αΛ describes the expansion of the grating, both due to temperature. Fig. 9: Operation of the Fiber Bragg Grating sensor [32] Because an FBG responds to both strain and temperature, you need to account for both effects and distinguish between the two. For sensing temperature, the FBG must remain unstrained. You can use packaged FBG temperature sensors to ensure the FBG inside the package 3 Fiber Bragg Grating Sensors is not coupled to any bending, tension, compression or torsion forces. The expansion coefficient αΛ of glass is For decades, for measuring mechanical and physical practically negligible. Thus, changes in the reflected phenomena electrical sensors have been used. These wavelength due to temperature can be primarily described sensors have intrinsic borders like susceptibility to by the change in the refractive index αn of the fiber. FBG

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strain sensors are more complex because both 4 Applications of FBG sensors: temperature and strain influence the sensor’s reflected wavelength. For proper strain measurements, you must compensate for the temperature effects on the FBG. You 4.1 FBG Sensors for Bridges can accomplish this by installing an FBG temperature sensor in close thermal contact with the FBG strain The highway bridge was first monitoring demonstrations sensor. A simple subtraction of the FBG temperature for large structures that utilize carbon fiber-based sensor wavelength shift from the FBG strain sensor composite pre-stressing tendons in the place of wavelength shift removes the second expression of steel-based tendons to resolve the problem of corrosion equation (2), yielding a temperature compensated strain [36]. In steel and concrete structures there is significant value. interest to monitor the deformation and strain for this The process of mounting an FBG strain gage is composite materials are not well proven, so that similar to mounting conventional electrical gages and fiber-optic sensing system are used. FBG sensors could be FBG strain gages are available with a variety of form suitable for achieving such a goal. Though, if the Fiber factors and mounting options including epoxy, wieldable, Bragg Grating sensors can be rooted into the composite bolt-on and embedded. The wavelength position tendons through their fabrication shelter for the sensors conversion method is shown in fig. 11. and their leads would be provided[37]. A FBG temperature sensor was installed in the each girder to allow for correction of thermally induced strain. A four-channel demodulation system has been developed based on the Erbium-doped fiber laser and combination of the linear filter method. In this a length of Erbium-doped optical fiber is pumped with the help of semiconductor laser at 980 nm serves as the fiber laser whose wavelength can be tuned by the wavelength shift of the sensing and sensing FBG the FBG induced by strain change is detected by the linear filter that converts the wavelength shift into intensity change [35]. Two similar FBG sensor systems using a long-period fiber grating [38] and a chirped fiber grating as wavelength discriminating elements for demodulating the sensor output have been used for replacement of the bulk linear filter and have Fig. 10: Wavelength-Position Conversion Method of FBG been field-tested for strain monitoring of concrete bridges Optical Sensors recently [39]. The two approaches provide an all-fiber and robust design. In order to obtain more detailed information about the strain distribution in a bridge structure due to damage, an FBG sensor system with up to 60 FBGs has been embedded into a 14 scale bridge model by the Naval Research Laboratory in USA [37]. This system with a typical response time of 0.1 s is well suited for static strain mapping but not for dynamic strain measurement, due to the constraint of the scanning speed of the Fabry Perot tune able filter used for the wavelength-shift measurement. This configuration combines FBGs with all-fiber Fabry Perot interferometric sensors. For a single sensor design, the phase change of the FFPI is used for high-sensitivity dynamic strain measurement whilst the wavelength shift of one of the two FBGs protected against strain are used for correction of thermal apparent strain. The wavelength deference between the two FBGs caused Fig. 11: FBG sensors for strain monitoring of a bridge[35] by a temperature gradient would be a problem for practical applications as it would degrade the visibility of the interferometric signal. Also, as the gauge length of the This method can be fast, simultaneous measurements sensor is normally much less than the size of the structure of all Fiber Bragg Grating in the array, but it offers limited to be monitored, the wavelength deference caused could SNR and resolution. The most important applications of be negligible due to small environmental temperature the Fiber Bragg Grating sensors are: gradients between the two FBGs.

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Static strain monitoring is simply obtained by directly 4.3 FBG sensors for Aircraft measuring the wavelength shift of another FBG sensor that is arranged in tandem nearby the FFPI and has a Aerospace structures are normally used the Advanced different central wavelength to the FBGs in the FFPI, materials for manufacturing engineering structures although it can also be achieved by the identification of Compared with metallic materials, advanced composite the central fringe position of the interferometric signal materials can have higher fatigue resistance, lighter when the FFPI is interrogated with a scanned local weight, higher strength-to-weight ratio, capability of receiving interferometer [40]. This FFPI/FBG obtaining complex shapes and no corrosion. Hence, to combination allows simultaneous measurement of three reduce the weight composite materials are used with FBG different parameters static strain, temperature and systems, maintenance cost of aircraft thus to improve in transient strain. Multiple FFPI/FBG sensor pairs are the performance [45]. Though, there is a important wavelength multiplexed for facilitating quasi-distributed challenge is monitoring in service and realizing real-time measurement. health usage with an on-board sensor system. For such an application a distributed FBG sensor system is used [46]. Because FBG sensors are sensitive to temperature and strain, it is very essential to calculate the temperature and strain simultaneously to rectify the thermal strain and static strain measurement. Many approaches have been proposed for simultaneous measurement of temperature and strain [47]. A simple method to utilize an unstrained temperature reference Fiber Bragg Grating, but this is not appropriate for all cases, e.g. FBG sensors embedded in composites. This may due to three possibilities: (i) in a multiplexed system to achieve sufficient strain and temperature discrimination accuracy with the dual parameter method is required. (ii) To obtain high spatial resolution it is required to integrate both strain and temperature sensors into the same location.(iii) if the FBG is large it processing the distorted FBG signal. Local and accurate temperature compensation for static strain measurement with FBG sensors in composites is problem to be solved [48]. At this stage it is easier to calculate Fig. 12: Wavelength division multiplexed FBG/FFPI sensor dynamic strain rather than static strain as temperature system[41] variations are normally much slower than dynamic strain changes and hence would not elect the measurement accuracy.

4.4 FBG sensors for the electric power industry 4.2 FBG Sensors for Mines Due to the protection to electro-magnetic interference FBG sensors are superlative for utilize in the electrical It is essential to monitor the displacement changes and power industry. In addition, FBGs can be used for measurement of load in underground excavations of long-distance distant operation is possible because of the mines and tunnels. Multiplexed Fiber Bragg Grating sensors can be able to replace the conventional electrical low transmission loss in the fiber. Winding temperature of electrical power transformers, loading of power sensors like load cells and strain gauges that cannot be transmission lines and large electrical currents have been work on a simple multiplexed fashion and in a very risky calculated with the Fiber Bragg Grating sensors [49]. environment with strong electro-magnetic interference generated by excavating machinery [42]. An Fiber Bragg Grating sensor system based on a Erbium-doped fiber source and a tune able Fabry Perot filter has been 4.5 Monitoring of power transmission lines designed for long-term static displacement measurement in the roof of the mining excavations and in the hanging The mechanical load on power transmission lines, which wall of the ore body’s mineshaft [43,44]. A specially may be occurred by heavy snow, e.g. in the hilly areas, designed extensometer with a mechanical level there is no simple access for assessment. Thus, an on-line mechanism can handle with the huge displacements of up measurement system is required to monitor the altering to a few cm. load on the electrical power line. The load is converted

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into strain by a metal plate which is attached to the line and onto which the Fiber Bragg Grating is bonded [50]. Many more sensors are required for such an application. Wavelength Division Multiplexing may no longer able to handle with the significant increase in sensor As the distance between adjoining Fiber Bragg Grating is large, high-speed modulation and demodulation would not necessary.

Fig. 14: Multi-channel FBG temperature sensor system. with super luminescent diode; avalanche photodiodes; low-pass filter; analogue-to-digital converter[53]

resolution detection of the wavelength-shifts induced by temperature changes are achieved using drift-compensated interferometric detection whereas the return signals from the FBG sensor array are demultiplexed with a simple monochromatic [54]. A strain-free probe shown in the inset of Fig. 14 is designed by enclosing the Fiber Bragg Grating sensor array in a protection sleeve. Fig. 13: Schematic diagram of FBG load monitoring system for The internal diameter of the sleeve is small hence it power transmission lines [51] can support large transverse stress without transferring it to the fiber. The inner diameter is selected to be a few times larger than the diameter of the fiber so that the inner surface of the sleeve does not contact the fiber under the maximum transverse stress condition [53]. The fiber link 4.6 Winding temperature measurement is connected to the processing unit via a fiber connector, making the probe disposable and interchangeable. A To understand the operation and verification of new or resolution of 0.13C and an accuracy of 0.23C over a modified products, Knowledge of the local temperature temperature range of 30-603C have been achieved, that distribution present in high-voltage, high power meet or exceed the requirements for many medical equipment like generators and transformers, is essential. applications. Defective or degraded equipment can be detected by Another FBG temperature sensor system using a continuously monitoring the variations in the winding tunable Fabry Perot filter has been developed for temperature that rejects the performance of the cooling achieving both WDM and wavelength-shift detection system. The FBG sensor has been demonstrated for such simultaneously, making the system simple and compact an application where the winding temperature of a as depicted in Fig. 15 [55]. The performance of the probe high-voltage transformer is measured with two 1550 nm with four sensing FBGs is tested by placing it in a FBGs as sensing and reference elements interrogated via container inside a NMR machine with a high magnetic a standard optical spectrum analyzer [52]. field of 4.7 T. With the help of thermal cross-talk between Fiber 4.7 Temperature Bragg Grating the spatial resolution can be determined along to the connecting fiber. Due to the complexity of the A novel FBG temperature sensor system has been specific heat transfer conditions it is not simple to verify demonstrated, as shown in Fig. 14, in which high the precise value of the resolution, although, experiments

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other type of applications with invention of large photo sensitivity in different material system.

References

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displacement measurement system integrated in an active Amit Grover became structural control system, Vol. 11, 2012, pp. 1125–1132. a Member (M) of Association ISTE in 2006, a Senior Member (SM) of society SELCOME in September Sanjeev Dewra was 2009, and a Project-In born in Panagarh (West charge (PI) in august Bengal), India, on October 2011 and in September 2012. 22, 1971. He received a B.E The author place of birth (Electronics & Telecomm.) is Ferozepur, Punjab, India on degree from Mahatma 27th,September 1980.The author received his M. Tech Gandhi Missions College degree in Electronics and Communication Engineering of engineering & technology, from Punjab Technical University, Kapurthla, Punjab, Marathwada University, India in 2008 and received his B. Tech degree in Aurangabad (M.S) in 1993 Electronics and Communication Engineering from Punjab and a M.E. degree from GNDEC, Ludhiana in 2002.He is Technical University, Kapurthala, Punjab, India in 2001. Ph.D. degree from Thapar University, Patiala (Punjab). Currently, he is working as an Assistant Professor in His field of interest is optical add drop multiplexer & Shaheed Bhagat Singh State Technical Campus, optical cross connect for optical communication systems. Ferozepur, Punjab,India. The author is a Reviewer of He has published various research papers in international many Reputed International Journals. His area of journals & conferences. Mr. Dewra is a life member of interest includes signal processing, MIMO systems, the Indian Society for Technical Education, Institution of Wireless mobile communication; high speed digital Engineers (India). He has over 20 years of Education communications, 4G Wireless Communications and Experience. He served as lecturer in Saint Kabir Institute VLSI Design. of Pharmaceutical & Technical Education, Fazilka from 1994 to 1998. He then joined Lala Lajpat Rai Institute of Engineering & Technology, Moga as a lecturer in 1999. In 2000, he joined Giani Zail Singh College of Engineering & Technology, Bathinda (Punjab) as Lecturer in the Department of Electronics and Communication Engineering and continued till 2003. In 2003, he joined as a Lecturer in the Electronics and Communication Engineering Department in Shaheed Bhagat Singh College of Engineering and Technology, Ferozepur (Punjab) & became a senior Lecturer in 2005. Presently he is working as an Assistant Professor & Head of ECE Department in the same college.

Vikas was born in Hoshiarpur, Punjab, India, on 1 6 Nov., 1991. HE obtained his Bachelor’s degree in Electronics and Communication Engineering from GGSCMT, kharar, Punjab, India. He is currently an M.Tech scholar in Electronics and Communication Engineering Department at Shaheed Bhagat Singh State Technical Campus Ferozepur, Punjab, India. His research mainly focuses on Communication.

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